1. Field
Example embodiments relate to an apparatus and method for sensing a failure with respect to a plurality of light emitting diode (LED) strings.
2. Description of the Related Art
A Light Emitting Diode (LED) corresponding to a light emitting device may have been developed in a form wherein a chip may have a predetermined size, for example, 1×1 mm2, because of a current injection limit, and the like.
According to recent improvement in light emitting efficiency, the LED has been widely applied from an initial signal display to a light source of a large display apparatus such as a Back Light Unit (BLU) and a Liquid Crystal Display (LCD), and lighting, since the LED consumes less power and lasts longer in comparison with a conventional lighting such as a light bulb and a fluorescent light.
Accordingly, there is a need for multiple LED chips to be manufactured in an array form so that the multiple LED chips may be used in an application outputting large amounts of light, for example, a lighting, a headlamp, and the like that may produce a high light output.
In this instance, an LED string may be manufactured and used by connecting a plurality of separate LED chips in series or in parallel through a wire bonding scheme, or by connecting LED chips on the same substrate through a special process.
Generally, an LED array may include a plurality of strings, and all of the LED strings may need to be connected in series in order to block a power supply of the entire LED when a failure occurs with respect to at least one LED.
In the case that all of the LED strings are connected in series, when an input voltage is lower than a forward voltage drop Vf of the entire LED, a boost circuit may be needed to be applied and accordingly costs may be increased, and an electro-magnetic compatibility (EMC) noise may occur.